Hi @Nicola_Band - multi-lingual is tricky. On the one hand you would like to have a community that can coalesce around a brand or topic of interest or practice, yet frankly language/country/culture provides its own sense of community as well.
Conceptually the idea of being language agnostic is compelling, but in practice is rather difficult. It does depend though upon the language/culture. If you think your majority of members will be English speaking, fine, we’ve seen that others will contribute periodically in other languages and the community will use tools like Google Translate and the interactions work, it’s good enough to get the gist of the conversation. You can embed the Google or Bing translation widgets on your site, then both 1) track usage and 2) ask the community what they think. Not bad for reading conversations; however, if you want to actively engage with speakers of several/many other languages, and you try to map out how an onboard translation technology might work in a threaded conversation, I’m not convinced it is very effective (happy to hear I’m wrong - anyone?) because as mentioned above, there is a strong sense of community which arises simply from shared language/country/culture, and with each iteration of machine translation from one language to another, the quality degrades.
I know a bit of a wishy/washy answer, in short from what I know and have experienced, there is not yet a great solution to this; I think we will see it in the next 5 years or so, but we’re still a ways off from a Star Trek universal translator. However, there are some interesting examples like this one from Skype - http://www.skype.com/en/translator-preview/
Happy to chat further on this topic